Door check attachment

ABSTRACT

A device adaptable for attachment to a pneumatic or hydraulic door check unit, which serves to keep a fully opened door in that position, until subsequently released. The device consists of a latching mechanism in which a pivotably mounted hooked member is directed by lateral pressure of a trigger member responsive to the motion of the door into the position in which the hooked member will latch on the initial return stroke to retain the door in the open position. The latching effect on the hooked member creates lateral motion, such that upon further opening motion of the opened door, the trigger member acts to move the hooked member away from the latching position so that on the second return stroke, the hooked member is free of latching engagement, and permits the door to close.

United States Patent [191 Stoffregen Jan. 15, 1974 [541 DOOR CHECK ATTACHMENT 1,188,996 4/1970 Great Britain 292 010. 4 [76] Inventor: Gunter Stoffregen, 16 Davis Downs Pl., Westhill, Ontario, Canada Gay Assistant Examiner-Peter A. Aschenbrenner F1led: Jan. 27, 19 AttorneyRobert L. Westell et al. [211 Appl. No.: 221,300

' [57] ABSTRACT 52 US. c1 16/49, 292/1310. 4, 16/66 A device adaptable for attachment to a Pneumatic or 51 Int. Cl E05f 3/00 hydraulic door Check unit, which Serves to keep a fully [58] Field of Search 16/49, 70, 85, 82, Opened door in that Position, unt l subsequently re- 16/66; 2 4 leased. The device consists of a latching mechanism in which a pivotably mounted hooked member is di- 5 References Cited rected by lateral pressure of a trigger member responsive to the motion of the door into the position in UNITED STATES PATENTS which the hooked member will latch on the initial reg t z et turn stroke to retain the door in the open position. n n s The latching effect on the hooked member creates lat- 2,8l7,554 12/1957 Hasselmark..... 292/DlG. 4 1509380 9/1924 Robertson 292mm. 4 eral mot1on, such that upon further openmg m0t1on of 1,114,675 10/1914 Blomeen 292 010. 4 the Opened door, the trigger member acts to move the 2,637,576 5/1953 Nottingham 292/1310. 4 hooked member y from the latching Position 89 1,493,794 5/1924 Robertson 292/D1G. 4 that on the second return stroke, the hooked member 265,919 10/1882 Elliott 16/66 is free of latching engagement, and permits the door FOREIGN PATENTS OR APPLICATIONS to close' 938,467 I/1956 Germany 292/D1G. 4 1 Claim, 7 Drawing Figures DOOR CHECK ATTACHMENT SUMMARY OF THE INVENTION This invention relates to a device for retaining a door in the opened position, while permitting the door to close under spring action, after a pulse of further opening pressure on the door.

An advantage of this invention is that the device may be installed, in parallel fashion, to an existing hydraulic or pneumatic door check device.

The device consists of an assembly which is adaptable to be mounted externally to the conventional tubular pneumatic or hydraulic door check unit. A movable slide member is fastened to the door check unit so as to slide longitudinally in response to the door movement. The slide member has a latch member integrally fastened to its mid-section inside the device, and terminates internally in a tapered pin which is longitudinally pointed inwards towards the external end of the slider. A hook member is loosely pinned inside the device with restricted motion in the longitudinal direction, but with free lateral travel, subject to a weak restraining spring.

In operation, opening of the door to which the device is attached creates longitudinal movement of the slide member, with the attached latched member brushing past the longitudinally fixed hook member, and moving the hook member laterally so that it will catch against the latch member on the return stroke of the slide member. When the door reaches the fully opened position, the latch member has completely passed the hook member, but the hook member is restrained from lateral motion by engagement with the tapered pin of the slide member. Thus, as the door is released manually from the fully open position, the hook member engages the latch of the slide member preventing further longitudinal motion of the slide member and restraining the door in the open position.

Further manual pressure on the door in the opening direction, frees the latch member from the hook member, but the hook member is now pushed laterally by the taper pin of the slide member to the position in which it is clear of engagement with the latch, so that the door is free to close.

BRIEF DESCRIPTION OF THE DRAWING The objects and features of the invention may be understood with reference to the following detailed description of an illustrative embodiment of the invention, taken together with the accompanying drawing in which:

FIG. 1 is a top plan view of the device mounted to a tubular door check;

FIG. 2 is a partial front view cross-section of the device;

FIG. 3 is an end view in cross-section taken at line 3-3 of FIG. 2;

FIG. 4 is a front cross-section of the device, with the attached door being opened;

FIG. 5 is a front cross-section of the device with the attached door fully opened, the door being manually held;

FIG. 6 is a front cross-section of the device with the attached door held by the device in the open position;

FIG. 7 is a front cross-section of the device with the sition,

DESCRIPTION OF THE PREFERRED EMBODIMENT:

Turning now descriptively to the drawing, in which similar reference characters denote similar elements through the several views, FIG. 1 illustrates the device 10 fastened by clamps 12 around legs 16 of the housing of a conventional door check unit 11, with sliding member 13 of the invention fastened to the piston rod 14 of the door check unit 11 by means of a mounting fastener through common hole 15.

In describing the operation of the device 10, it will be presumed that the device 10 is fastened to a door which may be manually opened to the full travel of the door check 11 or the door itself, a state which will be called the fully opened condition of the door, and that spring means when manual pressure is released exist to close the door, subject to the restraining action of the invention 10.

FIG. 2 and FIG. 3 illustrate the hook member 20 which is loosely fastened by riveted pin 21 so as to pre vent longitudinal movement. Hook member 20 may move in a lateral direction, but is normally kept in parallel alignment to the axis of the device 10 by coil spring 22. Hook member 20 terminates at the free end in a hook 24. Washers 23, also pinned by rivet 21 on each side of hook member 20, limit the angular twist with relation to rivet 21 that may be imparted to hook member 20.

As shown in FIG. 4-7, slide member 13 moves longitudinally to the right, in the illustrations, when the attached door is being opened, and to the left when the attached door is being closed. Restriction of the motion of slide member 13 in the closing direction by engagement with hook member 20 prevents closing motion of the attached door.

Shaped projecting cam 17, integrally fastened to slide member 13, has a wedge shaped leading edge 31 and a concave trailing edge 32. The wedge shaped leading edge 31 is set so as to interfere with hook member 24 and force the hook end 24 of book member 20 in a lateral direction against the reacting force of coil spring 22, when the slide member 13 is moving in the door opening direction, as shown by FIG. 5. After projecting cam 17 passes hook member 20 in the door opening direction, hook member 20 is restrained from returning to its normal resting position by engagement of hook member 20 with pin member 18 fastened to the end of slide member 13, as shown by FIG. 5.

Upon initial release of the fully opened door, FIG. 6 illustrates the manner in which the hook member 20, released from engagement with pin 18, starts to laterally return to its normal position parallel to the longitudinal axis of the device 10, but hook member 20 is latched by the concave trailing edge 32 of cam 17 on the reverse stroke of slide 13, preventing further closing motion of slide member 13 and the attached door.

Manually directed pressure on the door again towards the fully opened position, as seen in FIG. 7, reengages pin 18, attached to slide member 13, with hook member 20, but because of the location of the taper 37 on cam 17 and the point of 34 pin 18, with relation to the concave trailing edge 32 of cam 17, pin 18 now engages hook member 20 so as to laterally move it away from interference with cam 17 and in the direction of its normal'resting'position determined by coil spring 22. Consequently,'upon manual release of the door,

slide member 13 and the door are free to return to the closed position, with wedge section 33 of the trailing edge of cam 17 pushing hook member 20 laterally away from interference with cam 17 on the return door closing stroke.

Since obvious changes may be made in the specific embodiment of the invention described herein, it is indicated that all matter contained herein is intended as illustrative and not as limiting in scope.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. A latching device, for attachment to a door check unit having a cylinder element and a piston element, and serving releasably to secure a door in an open position, comprising:

a pair of parallel elongated members comprising a cam carrying member attachable to one of the elements of the door check and a hook carrying member attachable to the other element of the door check, the two members being longitudinally slidable extendably or retractably one with respect to the other when the door check is extended or retracted;

the cam carrying member having fixed thereon a planar cam having a sloping leading edge, a concave trailing edge, and a pair of lateral edges defining the cam width;

the hook carrying member having an elongated hook element loosely mounted thereon for lateral pivotable movement with respect to the longitudinal sliding direction of the members against spring biasing means urging the hook member into a laterally offset position within the cam width, the hook element having a hook projecting laterally into the plane of the cam;

whereby (l) on initially extending the members the hook engages and rides over the leading edge of the cam against the action of the hook biasing means and the spring biasing means urges the hook laterally to engage the concave trailing edge of the cam on retracting the members to restrain the members from further retracting, and (2) on extending the members again the hook emerges from the concave trailing edge of the cam and the spring biasing means urges the hook laterally therefrom allowing the members to be fully retracted;

the latching device further including an elongated pin member lying in the plane of the cam and oriented in the sliding direction of the members, the pin being spaced rearwardly from the concave trailing edge of the cam, whereby the hook rides along the pin when overshooting the cam on the initial extension of the members and drops into the concave trailing edge of the cam on initial retraction of the members;

the hook carrying member further comprising a channel and the cam carrying member a bar slidable along the base of the channel, the hook element being mounted on the channel above the base thereof by a transverse rivet passing loosely through the hook element, a compression coil spring being carried by the pin on one side of the hook element, the spring bearing against the hook element and against the side of the channel. 

1. A latching device, for attachment to a door check unit having a cylinder element and a piston element, and serving releasably to secure a door in an open position, comprising: a pair of parallel elongated members comprising a cam carrying member attachable to one of the elements of the door check and a hook carrying member attachable to the other element of the door check, the two members being longitudinally slidable extendably or retractably one with respect to the other when the door check is extended or retracted; the cam carrying member having fixed thereon a planar cam having a sloping leading edge, a concave trailing edge, and a pair of lateral edges defining the cam width; the hook carrying member having an elongated hook element loosely mounted thereon for lateral pivotable movement with respect to the longitudinal sliding direction of the members against spring biasing means urging the hook member into a laterally offset position within the cam width, the hook element having a hook projecting laterally into the plane of the cam; whereby (1) on initially extending the members the hook engages and rides over the leading edge of the cam against the action of the hook biasing means and the spring biasing means urges the hook laterally to engage the concave trailing edge of the cam on retracting the members to restrain the members from further retracting, and (2) on extending the members again the hook emerges from the concave trailing edge of the cam and the spring biasing means urges the hook laterally therefrom allowing the members to be fully retracted; the latching device further including an elongated pin member lying in the plane of the cam and oriented in the sliding direction of the members, the pin being spaced rearwardly from the concave trailing edge of the cam, whereby the hook rides along the pin when overshooting the cam on the initial extension of the members and drops into the concave trailing edge of the cam on initial retraction of the members; the hook carrying member further comprising a channel and the cam carrying member a bar slidable along the base of the channel, the hook element being mounted on the channel above the base thereof by a transverse rivet passing loosely through the hook element, a compression coil spring being carried by the pin on one side of the hook element, the spring bearing against the hook element and against the side of the channel. 